MIMO systems in general utilize multiple antennae at both the transmitter and receiver to improve communication performance between the transmitter and receiver. MIMO systems may allow for the communication of different information on each of a plurality of antennae via the transmitter, even using the same frequency. These MIMO systems may compensate for both frequency and time discrepancies. Exemplary systems that utilize MIMO technology include, but are not limited to, wireless Internet service providers (ISP), worldwide interoperability for microwave access (WiMAX) systems, and 4G long-term evolution (LTE) data transmission systems.
A master antenna may include a baseband radio and two chains of communication through vertically and horizontally polarized antennas. The master antenna may have a connection for power and data communications, typically shared through an interface such as power-over-Ethernet. A slave antenna connected by coaxial cable to the master antenna includes circuitry to compensate for cable loss and split the transmit and receive paths. The slave antenna provides communication over another pair of vertically and horizontally polarized antennae. With adequate physical separation between the pair of dishes on each end of a long distance link, a phase angle difference between the vertical and horizontal antenna elements allows four distinct channels of communication to occur as a result of MIMO processing.